The present invention is directed to ion generators and, more specifically, to an emitter assembly having outwardly extending ionizing pins. These ion generators are related generally to the field of devices that neutralize static charges in workspaces to minimize the potential for electrostatic discharge.
In many manufacturing and processing environments, it is desirable to prevent the accumulation of charge within a workspace. To prevent the accumulation of charge both positive and negative ions are guided into the workspace to neutralize any charge which may be building up. One example of an industry in which the accumulation of charge in production areas must be avoided is the disk drive industry where it is critical to maintain high manufacturing yields.
FIG. 1 shows, an emitter assembly 10xe2x80x2 of the type commonly used in ion air blowers. The emitter assembly 10xe2x80x2 is mounted so that air is propelled or drawn through an air guide 30xe2x80x2 which is formed by an annular ring 22xe2x80x2. Ionizing pins 32xe2x80x2 extend generally radially inwardly from the annular ring 32xe2x80x2 so that their tips are positioned in the air flow to allow ions to be blown or drawn off of the ionizing pins 32xe2x80x2 and out of the ion air blower (not shown) which houses the emitter assembly 10xe2x80x2.
It is common to use a fan (not shown) to drive or draw the air through the air guide 30xe2x80x2. The diameter of the area swept out by the fan blades of the fan assembly is approximately equal to the inner diameter of the annular ring 22xe2x80x2. Due to the position of the tips of the ionizing pins 32xe2x80x2 being proximate to the outer edge of the fan blades, the ions from the emitter assembly are released into a slower portion of the airflow generated by the fan.
Conventional emitter assemblies 10xe2x80x2 use relatively complicated point to point wiring 26xe2x80x2 to supply power to the ionizing pins 32xe2x80x2. The miniaturization of the ion air blower housing (not shown) which encloses the emitter assembly 10xe2x80x2 is limited by the size of the air guide 30xe2x80x2 of the emitter assembly 10xe2x80x2. Due to the high voltage being transferred through the wiring 26xe2x80x2 to the ionizing pins 32xe2x80x2, it is necessary that the housing of the ion air blower be spaced a minimum distance from the outside of the air guide 30xe2x80x2 to prevent the arcing or other leakage of electricity from either the pins 32xe2x80x2 or the wiring 26xe2x80x2 to the ion air blower housing (metal housings are preferred for electrical shielding purposes).
The size of the annular ring 22xe2x80x2 is also limited by the size of the fan to be used with the emitter assembly 10xe2x80x2. If the diameter of the annular ring 22xe2x80x2 is smaller than the diameter of the fan, then the amount of air forced through the air guide 30xe2x80x2 is reduced and the efficiency of the ion air blower is detrimentally effected.
The emitter assembly 10xe2x80x2 requires relatively complicated molding, tooling, and assembly of the annular ring 22xe2x80x2 to accommodate the wiring 26xe2x80x2 and the mounting of the ionizing pins 32xe2x80x2. In order to properly mount the ionizing pins 32xe2x80x2 on the annular ring 22xe2x80x2, it is necessary to manufacture sockets (not shown) for receiving the ionizing pins 32xe2x80x2 that are disposed within the body of the annular ring 22xe2x80x2. The tooling necessary to form the relatively complicated annular ring 22xe2x80x2 as well as the complicated point to point wiring and size limitations associated with the emitter assembly 10xe2x80x2 imposes several design limitations on devices using the emitter assembly 10xe2x80x2.
What is needed, but so far not provided by the conventional art, is an emitter assembly that is easy to manufacture, that allows an ion air blower incorporating the emitter assembly to be miniaturized without the risk of causing electrical arcs from the emitter assembly, that allows the ion air blower housing which encloses the emitter assembly to be miniaturized to a size comparable to that of the housing used by the fan of the ion air blower, and that facilitates the removal of ions from the ionizing pins by disposing the tips of the ionizing pins in the relatively faster portion of the airflow generated by the fan.
The present invention is an emitter assembly having outwardly extending ionizing pins. The emitter assembly of the present invention supports ionizing pins that extend generally radially outwardly from an annular assembly ring. The prior art recognized the use of ionizing pins supported by a ring structure; however, the prior art did not recognize that pointing the pins inwardly would be a limiting factor for reducing the size of the assembly.
The emitter assembly of the present invention is preferably, but not necessarily, used as part of an ion air blower and is preferably contained inside of an ion air blower housing. Also enclosed in the ion air blower housing is a fan that is used to force air or draw air over the ionizing pins. The ionizing pins extend from the outer surface of the annular assembly ring with the ionizing pin tips positioned in the air guide proximate to the point of fastest airflow generated by the fan blades. This facilitates the stripping of ions from the ends of the ionizing pins by the propelled or drawn air. Additionally, the generally outwardly orientation of the ionizing pins allows for the increased miniaturization of an ion air blower using the emitter.
The emitter assembly of the present invention also allows for simplified manufacturing and assembly. Because of the geometry and reduced complexity of the layout, it facilitates the use of a relatively simple mold for the manufacture. Further, by not requiring the central portion of the assembly to be open, an embodiment of the present invention reduces the complexity of the wire routing. Another embodiment eliminates conventional wiring altogether by utilizing pre-fabricated connectors, which may be a printed circuit board, for joining the ionizing pins to a power supply.